Consensus statement on Concussion in Sport—The 4th International Conference on Concussion in Sport held in Zurich, November 2012

Challenges and Research Opportunities for Integrating Quantitative Electroencephalography Into Sports Concussion Rehabilitation

Although concussion management and return to play/learn decision making focuses on reducing symptoms, there is growing interest in objective physiological approaches to treatment. Clinical and technological advancements have aided concussion management; however, the scientific study of the neurophysiology of concussion has not translated into its standard of care. This expert commentary is motivated by novel clinical applications of electroencephalographic-based neurofeedback approaches (eg, quantitative electroencephalography [QEEG]) for treating traumatic brain injury and emerging research interest in its translation for treating concussion. QEEG's low-cost relative to other brain recording/imaging techniques and precedent in clinical and medical care makes it a potential tool for concussion rehabilitation. Although uncommon, licensed and certified clinicians and medical professionals are implementing QEEG neurofeedback for concussion management within their score of practice. These approaches are not widely adopted nor recommended by professional medical societies, likely because of a limited evidence base of well-designed studies with available standard protocols. Thus, the potential efficacy of QEEG neurofeedback for treating persistent symptoms or cognitive dysfunction after sports-related concussion is unknown. This commentary will update the concussion clinician-scientist on the emerging research, techniques, and disagreements pertaining to the translation of QEEG neurofeedback for concussion management, particularly in the treatment of persistent cognitive difficulties. This commentary will also introduce to readers the fundamentals of how the electroencephalogram may be acquired, measured, and implemented during QEEG neurofeedback. An evidence base of supportive findings from well-designed studies, including those that are retrospective, outcomes-based, and, ultimately, placebo/sham-controlled is recommended prior to considering more widespread adoption of QEEG neurofeedback approaches for treating persistent symptoms or cognitive deficits after sports-related concussion. We review the considerable barriers to this research and clinical implementation, and conclude with opportunities for future research, which will be necessary for establishing the quality and efficacy of QEEG neurofeedback for concussion care.

Medical Coders' Use of the ICD-10-CM "Unspecified" Codes for Head and Brain Injury in Emergency Department Settings

CONTEXT

In the emergency department (ED) setting, prioritizing triage and patient care may lead to challenges in capturing detailed documentation necessary for specific International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) coding in medical records. Consequently, the prevalent use of the "unspecified head injury" code poses concerns about the precision of ED-based administrative billing claims data when analyzed for public health surveillance of nonfatal traumatic brain injuries (TBIs). Understanding the perspective of medical coders can illuminate coding processes and opportunities to enhance coding accuracy for TBI and other head injuries in the ED.

OBJECTIVE

This evaluation explores medical coders' perspectives and challenges when assigning ICD-10-CM codes to head injuries in the ED.

DESIGN

This qualitative evaluation utilized a phenomenological approach, which employed semi-structured interviews to understand medical coders' perspectives, processes, and coding determinations for head injuries in the ED.

SETTING

Interviews were conducted using a HIPAA-compliant video-based platform between July 2022 and January 2023.

PARTICIPANTS

Seventeen medical coders with ED coding experience were interviewed. Their backgrounds were diverse, though most had more than 15 years of experience.

MAIN OUTCOMES

Four qualitative themes emerged, which highlighted challenges with lack of detailed documentation, defaulting to unspecified codes, time, and productivity pressure, and additional insights into coders' assumptions and code determination processes.

RESULTS

Medical coders expressed challenges assigning ICD-10-CM codes to the highest level of specificity, citing issues including insufficient documentation by ED providers and terminology variations. Workplace time constraints and pressure for expedited claims also led to defaulting to unspecified codes.

CONCLUSIONS

This evaluation highlights the need for improved documentation consistency and detail in ED records to facilitate accurate ICD-10-CM coding. Alleviating time pressures, improving algorithms, and offering specialized training opportunities to medical coders could be helpful steps to improve coding specificity and data accuracy for head injuries in the ED.

Cervical spine sensorimotor deficits persist in people post-concussion despite minimal symptoms

BACKGROUND

The mechanisms of a concussion place stress on the cervical spine like that of a whiplash event, which can result in cervical spine dysfunction. This study aimed to determine if underlying cervical spine mobility and sensorimotor function deficits occur in individuals who are post-concussion with near resolution of symptoms.

METHODS

Twenty-five participants with a self-reported concussive event within a year (PC group: post-concussion 157 + 120 d, 9 men, age: 25 ± 8 yr) and 26 comparable peers (Peer group, 9 men, age: 25 ± 7 yr) were tested. The Post-Concussion Symptom Scale (PCSS) quantified residual concussion symptoms. Participants completed cervical joint position error (JPE) and cervical spine joint mobility tests blinded from each other. Group mean differences were analyzed using t-tests.

RESULTS

The PC group had minimal symptoms (PCSS = 6.8 ± 6.5) but substantial differences in JPE tests compared to the Peer group (PC = 7.4 ± 1.8 cm; PG = 5.6 ± 1.1 cm; p < .001). Those PC participants with pain during joint testing (n = 15) had worse JPE (Painful = 8.1 ± 1.8 cm, No-pain = 6.3 ± 1.6 cm; p = .02) and less averaged lower cervical spine joint mobility compared to PC participants without pain (Painful = 0.66 ± 0.22, No-pain = 0.87 ± 0.19; p = .02, Normal motion = 1.0).

CONCLUSION

Following a concussion, it is a reasonable recommendation to screen the cervical spine to identify impairments in joint mobility and JPE that contribute to neck dysfunction.

n-3 PUFA ameliorate functional outcomes following repetitive mTBI in the fat-1 mouse model

Purpose

Repeated mild traumatic brain injuries (mTBI) are a continuing healthcare concern worldwide, given its potential for enduring adverse neurodegenerative conditions. Past research suggests a potential protective effect of n-3 polyunsaturated fatty acids (PUFA) in experimental models of mTBI. The aim of this study was to investigate whether the neuroprotective benefits of n-3 PUFA persist following repetitive weight drop injury (WDI).

Methods

Male fat-1 mice (n = 12), able to endogenously convert n-6 PUFA to n-3 PUFA, and their wild type (WT) counterparts (n = 12) were maintained on a 10% w/w safflower diet. At 9-10 weeks of age, both groups received one mild low-impact WDI on the closed cranium daily, for three consecutive days. Following each WDI, time to righting reflex and seeking behaviour were measured. Neurological recovery, cognitive, motor, and neurobehavioural outcomes were assessed using the Neurological Severity Score (NSS) over 7 days (168 h) post-last WDI. Brains were assessed for cerebral microhemorrhages by Prussian blue and cellular damage by glial fibrillary acidic protein (GFAP) staining.

Results

Fat-1 mice exhibited significantly faster righting reflex and seeking behaviour time, and lower mean NSS scores and at all post-WDI time points (p ≤ 0.05) compared to WT mice. Immunohistochemistry showed no significant difference in presence of cerebral microhemorrhage however, fat-1 mice had significantly lower GFAP staining in comparison to WT mice (p ≤ 0.05).

Conclusion

n-3 PUFA is effective in restoring cognitive, motor, and behavioural function after repetitive WDI, which may be mediated through reduced cellular damage of the brain.

Effects of Different Recovery Duration on External and Internal Load Measures during Bouts of Small-Sided Games

The aim of this study was to analyse the effects of different recovery times between bouts of small-sided games (SSG) on external and internal load variables in semi-professional soccer players. Sixteen male semi-professional soccer players performed three 4 vs. 4 + goalkeeper SSG training sessions, each with different recovery bout duration: short (1 min) (SSG1), medium (2 min) (SSG2), and long (4 min) (SSG4). Time motion and neuromuscular measures were collected during all SSGs, in addition, the rating of perceived exertion (RPE) was determined at the end of the last bout of each SSG. Results showed a significant increase in the total number of accelerations (p = 0.016, ES = 0.97, large) and decelerations (p = 0.022, ES = 0.81, large) in SSG4 compared to SSG1. In terms of the internal load, SSG2 showed significantly higher RPE values (p = 0.011, ES = 1.00, large) in comparison with SSG1. If the sessions' focus is on neuromuscular training, longer recovery times between SSG bouts should be used. Conversely, if the aim is to reach a higher total and running distance at different intensities, a 2-min recovery period between bouts may be more appropriate.

Sports-Related Concussion Affects Cognitive Function in Adolescents: A Systematic Review and Meta-analysis

BACKGROUND

Rates of sports-related concussion (SRC) are high in adolescents. Ambiguity exists regarding the effect of SRC on cognitive function in adolescents.

PURPOSE

To rigorously examine adolescents' cognitive function after SRC.

STUDY DESIGN

Systematic review and meta-analysis; Level of evidence, 4.

METHODS

Web of Science, Scopus, and PubMed were searched from database inception until September 2021. Studies were included if participants were adolescents aged 13 to 18 years, if the definition of SRC was fully consistent with the Berlin Consensus Statement on Concussion in Sport, if the study included a control group or in-group baseline test, and if the study reported cognitive outcomes (eg, visual memory, processing speed) that could be separately extracted.

RESULTS

A total of 47 studies were included in the systematic review, of which 31 were included in the meta-analysis, representing 8877 adolescents with SRC. Compared with individuals in the non-SRC group, individuals with SRC had worse performance in cognitive function and reported more symptoms not only in the acute phase but also in the prolonged phase (1-6 months after injury) (visual memory: d = -0.21, 95% CI, -0.37 to -0.05, P = .012; executive function: d = -0.56, 95% CI, -1.07 to -0.06, P = .028; and symptoms: d = 1.17, 95% CI, 0.13 to 2.22, P = .028). Lower scores in most of the outcomes of cognitive function were observed at <3 days and at 3 to 7 days, but higher scores for verbal memory (d = 0.10; 95% CI, 0.03 to 0.17; P = .008) and processing speed (d = 0.17; 95% CI, 0.10 to 0.24; P < .001) were observed at 7 to 14 days after SRC relative to baseline. The effects of SRC on cognitive function decreased over time (100% of the variance in reaction time, P < .001; 99.94% of the variance in verbal memory, P < .001; 99.88% of the variance in visual memory, P < .001; 39.84% of the variance in symptoms, P = .042) in control group studies. Study design, participant sex, measurement tools, and concussion history were found to be modulators of the relationship between cognitive function and SRC.

CONCLUSION

This study revealed that adolescent cognitive function is impaired by SRC even 1 to 6 months after injury. Results of this study point to the need for tools to measure cognitive function with multiple parallel versions that have demographically diversiform norms in adolescents. Effective prevention of SRC, appropriate treatment, and adequate evaluation of cognitive function before return to play are needed in adolescent SRC management. Moreover, caution is warranted when using the baseline-to-postconcussion paradigm in return-to-play decisions.

Longitudinal, prospective study of head impacts in male high school football players

INTRODUCTION

Repetitive, subconcussive events may adversely affect the brain and cognition during sensitive periods of development. Prevention of neurocognitive consequences of concussion in high school football is therefore an important public health priority. We aimed to identify the player positions and demographic, behavioral, cognitive, and impact characteristics that predict the frequency and acceleration of head impacts in high school football players.

METHODS

In this prospective study, three cohorts of adolescent male athletes (N = 53, 28.3% Hispanic) were recruited over three successive seasons in a high school American football program. Demographic and cognitive functioning were assessed at baseline prior to participating in football. Helmet sensors recorded impact frequency and acceleration. Each head impact was captured on film from five different angles. Research staff verified and characterized on-field impacts. Player-level Poisson regressions and year-level and impact-level linear mixed-effect models were used to determine demographic, behavioral, cognitive, and impact characteristics as predictors of impact frequency and acceleration.

RESULTS

4,678 valid impacts were recorded. Impact frequency positively associated with baseline symptoms of hyperactivity-impulsivity [β(SE) = 1.05 impacts per year per unit of symptom severity (1.00), p = 0.01] and inattentiveness [β(SE) = 1.003 impacts per year per T-score unit (1.001), p = 0.01]. Compared to quarterbacks, the highest acceleration impacts were sustained by kickers/punters [β(SE) = 21.5 g's higher (7.1), p = 0.002], kick/punt returners [β(SE) = 9.3 g's higher (4.4), p = 0.03], and defensive backs [β(SE) = 4.9 g's higher (2.5), p = 0.05]. Impacts were more frequent in the second [β(SE) = 33.4 impacts (14.2), p = 0.02)] and third [β(SE) = 50.9 impacts (20.1), p = 0.01] year of play. Acceleration was highest in top-of-the-head impacts [β(SE) = 4.4 g's higher (0.8), p<0.001].

CONCLUSION

Including screening questions for Attention-Deficit/Hyperactivity Disorder in pre-participation evaluations can help identify a subset of prospective football players who may be at risk for increased head impacts. Position-specific strategies to modify kickoffs and correct tackling and blocking may also reduce impact burden.

Online youth concussion resources for Canadian teachers and school staff: A systematic search strategy

INTRODUCTION

Teachers and school staff (i.e., principals, coaches, trainers, educational assistants, guidance counselors, school healthcare professionals, etc.) are well positioned to support students' return-to-school post-concussion. Teachers and school staff may access concussion resources online as they are readily available; however, their quality and accuracy are unknown.

OBJECTIVE

To identify accurate online concussion resources suitable for Canadian teachers and school staff.

METHODS

A five-phased systematic search strategy was conducted: 1) initial identification of resources; 2) consultation of pediatric concussion experts; 3) inclusion and exclusion criteria; 4) content review; and, 5) material evaluation.

RESULTS

A total of 837 resources were identified initially and 40 resources were included in the final list. Across all resources, 310 (37%) resources were excluded as they were not designed primarily for teachers and school staff. Thirty-four (43%) of 80 resources reviewed for content accuracy were excluded. Among resources reviewed for readability, usability and suitability, six (13%) were excluded.

CONCLUSIONS

The 40 resources identified in this study can enable teachers and school staff to educate themselves about concussion and how to optimally support a student's return-to-school post-concussion.

Sports-Related Concussions in Adults Presenting to Canadian Emergency Departments

OBJECTIVE

To document the occurrence and recovery outcomes of sports-related concussions (SRCs) presenting to the Emergency Department (ED) in a community-based sample.

DESIGN

A prospective observational cohort study was conducted in 3 Canadian hospitals.

SETTING

Emergency Department.

PATIENTS

Adults (≥17 years) presenting with a concussion to participating EDs with a Glasgow Coma Scale score ≥13 were recruited.

INTERVENTIONS

Patient demographics (eg, age and sex), clinical characteristics (eg, history of depression or anxiety), injury characteristics (eg, injury mechanisms and loss of consciousness and duration), and ED management and outcomes (eg, imaging, consultations, and ED length of stay) were collected.

MAIN OUTCOME MEASURES

Patients' self-reported persistent concussion symptoms, return to physical activity status, and health-related quality of life at 30 and 90 days after ED discharge.

RESULTS

Overall, 248 patients were enrolled, and 25% had a SRC. Patients with SRCs were younger and reported more physical activity before the event. Although most of the patients with SRCs returned to their normal physical activities at 30 days, postconcussive symptoms persisted in 40% at 90 days of follow-up. After adjustment, there was no significant association between SRCs and persistent symptoms; however, patients with concussion from motor vehicle collisions were more likely to have persistent symptoms.

CONCLUSION

Although physically active individuals may recover faster after a concussion, patients returning to their physical activities before full resolution of symptoms are at higher risk of persistent symptoms and further injury. Patient-clinician communications and tailored recommendations should be encouraged to guide appropriate acute management of concussions.

Sleep Dysfunction in Adolescents With Prolonged Postconcussion Symptoms: A Reciprocal Coupling of Traumatic Brain Injury and Sleep-Related Problems

CLINICAL SCENARIO

Concussions are often neglected injuries that affect children and adolescents. Two physiological responses to a concussion are an ionic flux and an increased indiscriminate release of glutamate, which leads to an increase of intracellular calcium and extracellular potassium. This can ultimately result in sleep dysfunction, which often occurs after concussion and has long been thought of as simply another concussion symptom.

FOCUSED CLINICAL QUESTION

Does the likelihood of prolonged postconcussion symptoms increase with reported sleep-related problems (SRPs) in young athletes (8-18 y) compared to concussed young athletes without SRPs and healthy controls?

SUMMARY OF KEY FINDINGS

Four cohort studies with level 2/3 evidence measured subjective and objective sleep dysregulations in concussed and healthy populations. Overall, there was a difference in subjective SRPs between concussed and healthy patients. This correlated with other studies where worse sleep scores during the acute phase of concussion and increased SRPs led to worse ImPACT scores in patients 3 to 12 months postconcussion and longer overall recovery. Objective sleep dysfunction measures were significantly worse in concussed patients than in healthy controls, but no significant difference existed in melatonin measures.

CLINICAL BOTTOM LINE

There is strong evidence that sleep dysfunction is both a symptom of concussion as well as a causal factor of prolonged postconcussion symptoms. These studies show that sleep dysregulation is not always evident in objective measurements, leading to the strong possibility of a functional dysregulation of the sleep-wake cycle that is evident solely from subjective reports.

STRENGTH OF RECOMMENDATION

While there are strong cohort studies researching the role of sleep in those with postconcussion symptoms, the nature of sleep studies prevents the production of strong, high-level evidence studies such as randomized control trials. Thus, there is level B evidence that the likelihood of prolonged postconcussion symptoms is increased by a higher amount of SRPs.

Laboratory Validation of Instrumented Mouthguard for Use in Sport

Concussion is an inherent risk of participating in contact, combat, or collision sports, within which head impacts are numerous. Kinematic parameters such as peak linear and rotational acceleration represent primary measures of concussive head impacts. The ability to accurately measure and categorise such impact parameters in real time is important in health and sports performance contexts. The purpose of this study was to assess the accuracy of the latest HitIQ Nexus A9 instrumented mouthguard (HitIQ Pty. Ltd. Melbourne Australia) against reference sensors in an aluminium headform. The headform underwent drop testing at various impact intensities across the NOCSAE-defined impact locations, comparing the peak linear and rotational acceleration (PLA and PRA) as well as the shapes of the acceleration time-series traces for each impact. Mouthguard PLA and PRA measurements strongly correlated with (R² = 0.996 and 0.994 respectively), and strongly agreed with (LCCC = 0.997) the reference sensors. The root mean square error between the measurement devices was 1 ± 0.6g for linear acceleration and 47.4 ± 35 rad/s² for rotational acceleration. A Bland-Altman analysis found a systematic bias of 1% for PRA, with no significant bias for PLA. The instrumented mouthguard displayed high accuracy when measuring head impact kinematics in a laboratory setting.

Preliminary Evidence of a Dose-Response for Continuing to Play on Recovery Time After Concussion

OBJECTIVE

To investigate a dose-response relationship between continuing to play following concussion and outcomes.

PARTICIPANTS

A total of 130 athletes (age 11-19 years).

DESIGN

Repeated-measures design comparing symptoms, neurocognitive performance, and recovery time between 52 athletes immediately removed from play (Removed), 24 who continued to play for 15 minutes or less (Short-Play), and 32 who continued to play for more than 15 minutes (Long-Play).

MAIN MEASURES

Recovery was the number of days from injury to clearance. Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) measured neurocognitive outcomes and the Post-Concussion Symptom Scale (PCSS) measured symptom severity.

RESULTS

Long-Play (44.09 ± 27.01 days) took longer to recover than Short-Play (28.42±12.74 days) and Removed (18.98 ± 13.76 days). Short-Play was 5.43 times more likely, and Long-Play 11.76 times more likely, to experience protracted recovery relative to Removed. Both Play groups had worse neurocognitive performance and higher symptom scores than Removed at days 1 to 7, with Long-Play demonstrating worse reaction time than Short-Play. At days 8 to 30, both Play groups performed worse than Removed on visual memory and visual motor speed, while only Long-Play performed worse on verbal memory and reaction time.

CONCLUSIONS

Results provide initial evidence of a dose-response effect for continuing to play on recovery from concussion, highlighting the importance of removal from play.

The Role of Active Rehabilitation in Concussion Management: A Systematic Review and Meta-analysis

PURPOSE

This study aimed to conduct a systematic review and meta-analysis of active rehabilitation on concussion management. We also examined moderator variables that may contribute to differences across studies: symptom scale, physical activity type, time of injury to recruitment, and mechanism of injury.

METHODS

The standardized effect size of physical activity on concussion management was computed for 23 studies (29 effect sizes). Effect sizes were coded as positive when studies reported an improvement in symptom scores, which was represented by a decrease in postconcussive symptom scores.

RESULTS

The overall effect size of physical activity on concussion recovery was large and positive (g = 1.03). Subthreshold aerobic activity provided the largest effect size (g = 1.71), whereas multimodal interventions had a moderate effect size (g = 0.70). All other moderator variables produced positive effect sizes ranging from g = 0.59 to g = 1.46.

CONCLUSIONS

This systematic review and meta-analysis demonstrates that current evidence supports the notion that physical activity is beneficial in decreasing postconcussive symptoms in both the acute and chronic phases after concussion. The results indicate that unimodal subthreshold aerobic activity may be the best course of action compared with multimodal interventions. Despite this growing body of evidence, additional research is needed to determine the optimal intensity, duration, and time to initiation of aerobic exercise after concussion.

Visual effects of concussion: A review

A concussion occurs when a direct or indirect force is transmitted to the brain, causing a change in brain function. Given that approximately half the brain circuits are involved in vision and the control of eye movements, a concussion frequently results in visual symptoms. Ophthalmic abnormalities are helpful in the assessment of acute concussion, identified by rapid automized naming tasks and eye movement assessments. In particular, convergence, eye-tracking and the vestibular-ocular motor screening tool may be used. For patients suffering from post-concussion syndrome more than 3 months from the original injury, abnormalities may be found in convergence, accommodation and smooth pursuit. Orthoptic exercises are useful rehabilitation tools to allow patients to return to school, work and recreation. This article provides a brief overview of concussion as it relates to vision and ophthalmic practice.

Review of wearable technologies and machine learning methodologies for systematic detection of mild traumatic brain injuries

Mild traumatic brain injuries (mTBIs) are the most common type of brain injury. Timely diagnosis of mTBI is crucial in making 'go/no-go' decision in order to prevent repeated injury, avoid strenuous activities which may prolong recovery, and assure capabilities of high-level performance of the subject. If undiagnosed, mTBI may lead to various short- and long-term abnormalities, which include, but are not limited to impaired cognitive function, fatigue, depression, irritability, and headaches. Existing screening and diagnostic tools to detect acute andearly-stagemTBIs have insufficient sensitivity and specificity. This results in uncertainty in clinical decision-making regarding diagnosis and returning to activity or requiring further medical treatment. Therefore, it is important to identify relevant physiological biomarkers that can be integrated into a mutually complementary set and provide a combination of data modalities for improved on-site diagnostic sensitivity of mTBI. In recent years, the processing power, signal fidelity, and the number of recording channels and modalities of wearable healthcare devices have improved tremendously and generated an enormous amount of data. During the same period, there have been incredible advances in machine learning tools and data processing methodologies. These achievements are enabling clinicians and engineers to develop and implement multiparametric high-precision diagnostic tools for mTBI. In this review, we first assess clinical challenges in the diagnosis of acute mTBI, and then consider recording modalities and hardware implementation of various sensing technologies used to assess physiological biomarkers that may be related to mTBI. Finally, we discuss the state of the art in machine learning-based detection of mTBI and consider how a more diverse list of quantitative physiological biomarker features may improve current data-driven approaches in providing mTBI patients timely diagnosis and treatment.

Evaluation of CogSport for acute concussion diagnosis in cricket

Objective

The diagnosis of sport-related concussion is a challenge for practitioners given the variable presentation and lack of a universal clinical indicator. The aim of this study was to describe the CogSport findings associated with concussion in elite Australian cricket players, and to evaluate the diagnostic ability of CogSport for this cohort.

Methods

A retrospective study design was used to evaluate CogSport performance of 45 concussed (male n=27, mean age 24.5±4.5 years; female n=18, 23.5±3.5 years) compared with 45 matched non-concussed (male n=27, mean age 27.3±4.5 years; female n=18, 24.1±4.5 years) elite Australian cricket players who sustained a head impact during cricket specific activity between July 2015 and December 2019.

Results

Median number of reported symptoms on the day of injury for concussed players was 7 out of 24, with a median symptom severity of 10 out of 120. CogSport performance deteriorated significantly in concussed cricket players’ Detection speed (p<0.001), Identification speed (p<0.001), One Back speed (p=0.001) and One Back accuracy (p=0.022) components. These components, when considered independently and together, had good diagnostic utility.

Conclusion

This study demonstrated good clinical utility of CogSport for identifying concussed cricket players, particularly symptoms and Detection, Identification and One Back components. Therefore, CogSport may be considered a useful tool to assist concussion diagnosis in this cohort, and the clinician may place greater weight on the components associated with concussion diagnosis.

The role of diffusion tensor imaging in characterizing injury patterns on athletes with concussion and subconcussive injury: a systematic review

Traumatic brain injury (TBI) is a major public health problem. The majority of TBIs are in the form of mild TBI (also known as concussion) with sports-related concussion (SRC) receiving public attention in recent years.Here we have performed a systematic review of the literature on the use of Diffusion Tensor Imaging (DTI) on sports-related concussion and subconcussive injuries. Our review found different patterns of change in DTI parameters between concussed and subconcussed groups. The Fractional Anisotropy (FA) was either unchanged or increased for the concussion group, while the subconcussed group generally experienced a decrease in FA. A reverse pattern was observed for Mean Diffusivity (MD) - where the concussed group experienced a decrease in MD while the subconcussed group showed an increase in MD. However, in general, discrepancies were observed in the results reported in the literature - likely due to the huge variations in DTI acquisition parameters, and image processing and analysis methods used in these studies. This calls for more comprehensive and well-controlled studies in this field, including those that combine the advanced brain imaging with biomechancial modeling and kinematic sensors - to shed light on the underlying mechanisms behind the structural changes observed from the imaging studies.

A Normative Reference vs. Baseline Testing Compromise for ImPACT: The CARE Consortium Multiple Variable Prediction (CARE-MVP) Norms

BACKGROUND

Sports medicine clinicians routinely use computerized neurocognitive testing in sport-related concussion management programs. Debates continue regarding the appropriateness of normative reference comparisons versus obtaining individual baseline assessments, particularly for populations with greater likelihood of having below- or above-average cognitive abilities. Improving normative reference methods could offer alternatives to perceived logistical and financial burdens imposed by universal baseline testing.

OBJECTIVES

To develop and validate the Concussion Assessment, Research, and Education (CARE) Consortium Multiple Variable Prediction (MVP) norms for the Immediate Postconcussion Assessment and Cognitive Testing (ImPACT).

METHODS

We developed the CARE-MVP norms for ImPACT composite scores using regression-based equations. Predictor variables included sex, race (white/Caucasian, black/African American, Asian, or Multiple Races), medical history [attention-deficit/hyperactivity disorder (ADHD), learning disorder (LD), prior concussion(s), prior psychiatric diagnosis], and an estimate of premorbid intellect (Wechsler Test of Adult Reading). CARE-MVP norms were first validated in an independent sample of healthy collegiate athletes by comparing predicted and actual baseline test scores using independent-samples t-tests and Cohen's d effect sizes. We then evaluated base rates of low scores in athletes self-reporting ADHD/LD (vs. non-ADHD/LD) and black/African American race (vs. white/Caucasian) across multiple normative reference methods (Chi square, Cramer's V effect size). Lastly, we validated the CARE-MVP norms in a concussed sample (dependent samples t test, Cohen's d effect size).

RESULTS

A total of 5233 collegiate athletes (18.8 ± 1.2 years, 70.5% white/Caucasian, 39.1% female) contributed to the CARE-MVP norms (development N = 2616; internal validation N = 2617). Race and WTAR score were the strongest and most consistent ImPACT score predictors. There were negligible mean differences between observed and predicted (CARE-MVP) baseline scores (Cohen's d < 0.1) for all ImPACT composite scores except Reaction Time (predicted ~ 20 ms faster than observed, d = - 0.28). Low score base rates were similar for athletes across subpopulations when using CARE-MVP norms (ADHD/LD, V = 0.017-0.028; black/African American, V = 0.043-0.053); while, other normative reference methods resulted in disproportionately higher rates of low scores (ADHD/LD, V = 0.062-0.101; black/African American race, V = 0.163-0.221). Acute (24-48 h) postconcussion ImPACT scores were significantly worse than CARE-MVP norms but notably varied as a function of concussion symptom severity.

CONCLUSIONS

Results support CARE-MVP norm use in populations typically underrepresented or not adjusted for in traditional normative reference samples, such as those self-reporting ADHD/LD or black/African American race. CARE-MVP norms improve upon prior normative methods and may offer a practical, simple alternative for collegiate institutions concerned about logistical and financial burden associated with baseline testing. An automated scoring program is provided.

Nutritional factors in sport-related concussion

BACKGROUND

Sports concussion is a major problem that affects thousands of people every year. Concussion-related neurometabolic changes are thought to underlie neurophysiological alterations and post-concussion symptoms, such as headaches and sensitivity to light and noise, disabilities of concentration and tiredness. The injury triggers a complex neurometabolic cascade involving multiple mechanisms. There are pharmaceutical treatments that target one mechanism, but specific nutrients have been found to impact several pathways, thus offering a broader approach. This has prompted intensive research into the use of nutrient supplements as a concussion prevention and treatment strategy.

METHOD

We realised a bibliographic state of art providing a contemporary clinical and preclinical studies dealing with nutritional factors in sport-related concussion.

RESULTS

Numerous supplements, including n-3 polyunsaturated fatty acids, sulfur amino acids, antioxidants and minerals, have shown promising results as aids to concussion recovery or prevention in animal studies, most of which use a fluid percussion technique to cause brain injury, and in a few human studies of severe or moderate traumatic brain injury. Current ongoing human trials can hopefully provide us with more information, in particular, on new options, i.e. probiotics, lactate or amino acids, for the use of nutritional supplements for concussed athletes.

CONCLUSION

Nutritional supplementation has emerged as a potential strategy to prevent and/or reduce the deleterious effects of sports-related concussion and subconcussive impacts.

Effect on thickness of a single-layer mouthguard of positional relationship between suction port of the vacuum forming device and the model

BACKGROUND/AIM

Wearing a mouthguard reduces the risk of sport-related injuries, but the thickness has a large effect on its efficacy and safety. The aim of this study was to investigate the effect on the thickness of a single-layer mouthguard of the positional relationship between the suction port of the vacuum forming device and the model.

MATERIALS AND METHODS

Ethylene-vinyl-acetate sheets of 4.0-mm-thickness and a vacuum forming machine were used. Two hard plaster models were prepared: Model A was 25-mm at the anterior teeth and 20-mm at the molar, and model B was trimmed so the bucco-lingual width was half that of model A. Three model positions on the forming table were examined: (a) P20, where the model anterior rim was located in front of the suction port, (b) P30, where the model anterior rim and front edge of the suction port were close, and (c) P43, where the model anterior rim and palatal rim were located on the suction port. Six mouthguards were fabricated for each condition. Thickness differences due to model form and model position were analyzed.

RESULTS

Thickness differences due to model form were observed at the incisal edge and labial surface, and model A was significantly thicker than model B in P43 (P<.01). The thickness of the incisal edge and labial surface was significantly greatest in P43 for model A, but in P30 for model B.

CONCLUSIONS

The effect of the model position on the forming table on suppressing the labial thickness reduction of the mouthguard depended on the bucco-lingual width of the model. It is important to position the model anterior rim away from the sheet frame if the bucco-lingual width of the model is large and to place the model anterior rim in front of the suction port if the width is small.

Resilience and Sexuality After Concussion in Women

Background

Previous findings from our group show that in the acute (ie, 6–10 weeks) post-injury period, women with concussions have a 70% greater risk of sexual dysfunction than those with extremity injuries. There are currently limited treatment options for the clinical management of concussions. Resilience is a protective, modifiable psychological construct that has been shown to improve concussion-related sequelae. To date, however, no research has evaluated how resilience impacts sexuality outcomes after concussion in women.

Aim

Evaluate if resilience offers protection against negative sexuality outcomes in a cohort of reproductive, aged women with a concussion, seeking care in the Emergency Department of a Level-1 Trauma Center. We hypothesized that women with low resilience will be more likely to experience negative impacts on sexuality and that increasing levels of resilience will be associated with more positive sexuality outcomes.

Methods

Secondary data analyses.

Measures

Resilience was evaluated with the Resilience Scale (RS), and the Brain Injury Questionnaire for Sexuality (BIQS) was used for sexuality.

Results

Of the 299 participants recruited for the parent study, 80 with concussion had complete follow-up data and were included in these secondary analyses. Less than half (42.5%; n = 34) had low resilience (score≤130 on the RS), and the remaining 46 (57.5%) had high resilience (score>130 on the RS). In crude linear regression models, 1-unit increase in resilience was associated with a 4% increase in sexuality outcomes (β = 0.04, 95% CI:0.01, 0.05; P = .008). The effect estimate remained similar in post-concussion-symptom-adjusted models (β = 0.03, 95% CI:0.002, 0.06; P = .03). Mood-adjusted models showed a statistically significant interaction term (P < .0001). After stratifying by mood, findings showed that unit increases in resilience were associated with a 6% increase in sexuality outcomes for women in the high risk mood group (HADS score ≥11; PCS-adjusted β = 0.06, 95% CI:0.02, 0.11; P = .009).

Conclusion

Longitudinal studies are needed to evaluate how these improvements in resilience translate to patient recovery measures following concussion.

Anto-Ocrah M, Oktapodas Feiler M, Pukall C, et al. Resilience and Sexuality After Concussion in Women. Sex Med 2021;9:100297.

The influence of fatiguing exercise on Sport Concussion Assessment Tool (SCAT) scoring in a female pediatric population

There is currently a lack of information available about the effect that exercise fatigue may have on Child Sport Concussion Assessment Tool (SCAT) scoring in a pediatric population. Objective: The goal of this study was to examine the influence of a fatiguing bout of aerobic exercise on Child Sport Concussion Assessment Tool (SCAT) scoring in an adolescent female sporting population. Methods: A prospective, observational-based, test-retest study design was used to collect Child SCAT data from thirty healthy 9-12 year old physically active females during two testing sessions that occurred a minimum of 7 days apart. Within each testing session, each child completed a fatiguing bout of aerobic exercise, and the Child SCAT was administered: (1). Pre-exercise and (2). Post-exercise. Parametric and non-parametric testing was used to compare aerobic exercise test results and pre- vs. post-exercise Child SCAT data. Test-retest reliability was evaluated using intra-class correlation coefficient (ICC 3,1) analysis. Results: No significantly differences were noted between pre- and post-exercise Child SCAT data during either test day. ICC values suggested that a majority of the individual components of the Child SCAT demonstrated poor test-retest reliability. Conclusion: Clinicians using the Child SCAT as a sideline assessment tool during youth sport should have confidence that individual component scores are uninfluenced by aerobic exercise completed immediately prior to assessment. But, clinicians should also be cautioned against using Child SCAT data from consecutive testing days when making decisions about patient recovery and return-to-sport timelines.

Eye Tracking as a Biomarker for Concussion in Children

OBJECTIVE

Concussion is the most common type of brain injury in both pediatric and adult populations and can potentially result in persistent postconcussion symptoms. Objective assessment of physiologic "mild" traumatic brain injury in concussion patients remains challenging. This study evaluates an automated eye-tracking algorithm as a biomarker for concussion as defined by its symptoms and the clinical signs of convergence insufficiency and accommodation dysfunction in a pediatric population.

DESIGN

Cross-sectional case-control study.

SETTING

Primary care.

PATIENTS

Concussed children (N = 56; mean age = 13 years), evaluated at a mean of 22-week post-injury, compared with 83 uninjured controls.

INDEPENDENT VARIABLES

Metrics comparing velocity and conjugacy of eye movements over time were obtained and were compared with the correlation between Acute Concussion Evaluation (ACE) scores, convergence, and accommodation dysfunction.

MAIN OUTCOME MEASURES

Subjects' eye movements recorded with an automated eye tracker while they watched a 220-second cartoon film clip played continuously while moving within an aperture.

RESULTS

Twelve eye-tracking metrics were significantly different between concussed and nonconcussed children. A model to classify concussion as diagnosed by its symptoms assessed using the ACE achieved an area under the curve (AUC) = 0.854 (71.9% sensitivity, 84.4% specificity, a cross-validated AUC = 0.789). An eye-tracking model built to identify near point of convergence (NPC) disability achieved 95.8% specificity and 57.1% sensitivity for an AUC = 0.810. Reduced binocular amplitude of accommodation had a Spearman correlation of 0.752(P value <0.001) with NPC.

CONCLUSION

Eye tracking correlated with concussion symptoms and detected convergence and accommodative abnormalities associated with concussion in the pediatric population. It demonstrates utility as a rapid, objective, noninvasive aid in the diagnosis of concussion.

White Matter Abnormalities in Retired Professional Rugby League Players with a History of Concussion

The topic of potential long-term neurological consequences from having multiple concussions during a career in collision sports is controversial. We sought to investigate white matter microstructure using diffusion tensor imaging (DTI) in retired professional Australian National Rugby League (NRL) players (n = 11) with a history of multiple self-reported concussions compared with age- and education-matched controls (n = 13) who have had no history of brain trauma. Diffusion-weighted images were acquired with a Siemens 3T scanner. All participants completed a clinical interview. There were no significant differences between groups on measures of depression, anxiety, stress, or post-concussion symptoms; however, NRL players scored significantly higher on the alcohol use disorder identification test (AUDIT). Voxelwise analyses of DTI measures were performed using tract-based spatial statistics (TBSS) with age and AUDIT scores included as covariates. TBSS revealed significantly reduced fractional anisotropy (FA), and increased radial diffusivity (RD), axial diffusivity (AD), and trace (TR) in white matter regions of recently retired NRL players compared with controls. FA was significantly reduced in the right superior longitudinal fasciculus and right corticospinal tract while TR, RD, and AD were increased in these regions, as well as the corpus callosum, forceps major, right uncinate fasciculus, and left corticospinal tract. In summary, DTI in a small cohort of recently retired professional NRL players with a history of multiple concussions showed differences in white matter microstructure compared with age- and education-matched controls with no history of brain trauma.

Awareness and Perceived Value of Eye Tracking Technology for Concussion Assessment among Sports Medicine Clinicians: A Multinational Study

Objective: The awareness of concussion as a serious and frequently occurring sports injury and its management has evolved significantly. One viable objective diagnostic tool is eye tracking technology. The authors hypothesized that while clinicians may be aware that assessing eye movements in concussed athletes can be beneficial, it is possible that, due to the novelty of the eye tracking technology and limited exposure, only a few actually use it in their practice. The study aimed to assess the awareness of eye movement deficits associated with concussion amongst sports medicine clinicians and to determine the utilization and perceptions of the eye tracking technology for concussion diagnosis.Methods: An online 18-question survey was distributed internationally from January until December 2017 and completed by 171 sports medicine clinicians (sport physicians, therapists, general practitioners, neuropsychologists) from 32 countries.Results: Respondents indicated that subjectivity of assessments remained a major limitation of established diagnostic tools. Eye tracking technology, despite its potential to attenuate this limitation, was only used by 12% of respondents. To diagnose concussion, 77% did not use any eye movement assessment tools other than own clinical assessment. With the exception of abnormal pupil light reflex, which was checked by 68%, eye movement deficits were inspected by less than half of the respondents (46.3 ± 12%).Conclusion: Even among sports medicine clinicians who regularly attend to patients with concussions, there is insufficient awareness that concussion can lead to abnormal eye tracking behavior. Lack of exposure to the sensitive eye tracking equipment may be a limiting factor for using eye movement metrics for concussion diagnostics. Facilitating the awareness of objective methods, like eye tracking technology, may help assure the appropriate continuum of identification and treatment for concussed athletes. Increasing educational opportunities and practical experience of clinicians regarding concussive symptoms and potential innovative technology is strongly advocated.

Remote concussion history does not affect visually-guided reaching in young adult females

Aim:

We examined the long-term effects of concussions in young adult females on visuomotor behavior during a visually-guided reaching task of various complexities.

Materials & methods:

20 females with a history of longer than 6 months since a concussion and 20 healthy females quickly and accurately performed a delayed reach to a previously cued target.

Results:

As both cognitive and motor load increased, task performance decreased for both groups (p < 0.05). However, contrary to our primary hypothesis, no differences in task performance were found between the two experimental groups (p > 0.05).

Conclusion:

The young adult females with a remote history of concussion demonstrated no deficits in visuomotor behavior on an attention-mediated reaching task as compared with control participants.

Current literature is inconclusive regarding the long-term effects of concussion. Some have argued that the differing results are due to many uncontrolled factors in study design. In this study, 20 females with a history of concussion more than 6 months ago and 20 healthy females performed a reaching task under different levels of difficulty. As the reaching task got harder, both groups had greater difficulty doing the task quickly and accurately (p < 0.05). Surprisingly, however, no differences in reaching performance existed between the two groups (p > 0.05). Young adult females with a remote history of concussion demonstrated no greater problems with complicated reaching tasks when compared with control participants when experimental conditions are tightly controlled.

Academic aptitude mediates the relationship between socioeconomic status and race in predicting ImPACT scores in college athletes

Objective: To evaluate the influences of sociodemographic factors, estimated head impact exposure, and academic aptitude on ImPACT scores in college athletes.Methods: Data were reported on 18,886 participants (58% male) from the NCAA/DoD CARE Consortium. Race, SES, concussion history, estimated repetitive head impact exposure (eRHIE), and academic aptitude (SAT or ACT score) were our predictors of interest. Cognition was measured using ImPACT composite scores. We evaluated the mediating effects of academic aptitude on sociodemographic predictors and eRHIE on ImPACT scores. We then evaluated a football-only subsample and added age of first exposure to football (AFE) to the model. Males, females, and football players were analyzed separately using structural equation modeling.Results: Academic aptitude was associated with Black/African American race, SES, and each of the ImPACT composite scores. There were significant indirect effects of Black/African American race and SES on all ImPACT composite scores. Academic aptitude fully mediated SES effects and either fully or partially mediated race effects. Contrary to expectation, greater concussion history and eRHIE predicted better ImPACT scores.Conclusions: Academic aptitude, a stable indicator of premorbid cognitive function, consistently and most strongly predicted baseline ImPACT scores in collegiate student-athletes. Concussion and eRHIE history demonstrated a small positive, but non-significant, relationship with cognitive scores at the time of college athletic participation. This study suggests that attempts to characterize cognitive ability across the lifespan must consider premorbid functioning and sociodemographic variables.

Racial and Ethnic Differences in Emergency Department Utilization and Diagnosis for Sports-Related Head Injuries

Background: Prior studies have shown racial differences in concussion awareness and outcome.

Objective: To assess if racial or ethnic differences exist in Emergency Department (ED) utilization and diagnosis for children with sports-related head injuries.

Methods: We performed a retrospective, cross-sectional analysis of ED visits from 2008 to 2017 using National Electronic Injury Surveillance System (NEISS) data. Population-weighted ED visits for children age 7–18 years with a sport-related injury were included. We compared the probability of an ED visit being for an injury to the head or diagnosed as a concussion between children of different races/ethnicities. Analyses were adjusted for age, gender, sport, year, and location where the injury occurred.

Results: We identified 11,529,994 population-weighted ED visits for pediatric sports-related injuries, of which 1,497,717 (13.0%) were injuries to the head and 619,714 (5.4%) received a diagnosis of concussion. Black children were significantly less likely than non-Hispanic white children to have their ED visit be for an injury to the head [Odds Ratio (OR) 0.72, 95%CI 0.65–0.79] or concussion (OR 0.58, 95%CI 0.50–0.68). Black children presenting to the ED with an injury to their head were less likely than non-Hispanic white children to be diagnosed with a concussion (OR = 0.71, 95%CI 0.59–0.85).

Conclusions: Racial differences exist in both ED utilization for pediatric sports-related head injuries and in the diagnosis of concussion. Further work is needed to understand these differences to ensure all brain injured athletes receive optimal care, regardless of race.

A systematic review of acute concussion assessment selection in research

Background: Several organisations developed guidelines and assessments for aiding in the diagnosis of concussions. The growing number of concussion assessments increases the difficulty for researchers and clinicians to determine the best method of concussion diagnosis. Purpose: To systematically review the current assessments selected for acute sports-related concussion. Methods: Academic Search Premier, CINHAL, MEDLINE, PsycINFO and SPORTDiscus were searched. English-language, peer-review published studies of acute (<72 h) concussion assessments were included. Results: A total of 31 studies met inclusion criteria (of 291 evaluated); 27 studies provided sufficient information to be included in the descriptive statistics of the assessments. Six of these assessments were used in at least three studies. Only 12 percent of the population studied was female. The age range for these assessments was 9-67 years, although most participants ranged in age between 18 and 35 years. Conclusion: There is a need for a 'gold' standard concussion assessment to enable consistency across research and clinical outcomes. We found a large discrepancy between the number of males and females assessed, suggesting that future studies are needed to determine if these current assessments identify concussion signs and symptoms unique to females. Further studies are needed to determine which assessments are appropriate and valid for youth athletes.

Pain with traumatic brain injury and psychological disorders

Traumatic brain injury (TBI) is the cause for long-term disability in more than 3 million patients in the US alone, with chronic pain being the most frequently reported complain. To date, predisposing mechanisms for chronic pain in TBI patients are largely unknown. Psychological disorders, including post-traumatic stress disorder, depression and anxiety following TBI are commonly reported comorbidities to post-traumatic pain. Long term consequences can be debilitating and affect quality of life even when the injury is mild. In this review, we present the most commonly reported chronic pain conditions across the spectrum of severity of TBI, mainly focusing on mild TBI. We discuss chronic post- traumatic headaches, widespread pain as well as post-traumatic central pain. We discuss pain in the context of injury severity and military versus civilian populations. We are only starting to understand the biological mechanisms behind post-traumatic pain and associated psychological distress following TBI, with genetic, biochemical and imaging studies pointing to the dopaminergic, neurotrophic factors and the role of Apolipoprotein. Physiological and neurological mechanisms are proposed to partially explain this interaction between post-traumatic pain and psychological distress. Nevertheless, the evidence for the role of structural brain damage remains incomplete and to a large extent debatable, as it is still difficult to establish clear causality between brain trauma and chronic pain. Finally, general aspects of management of chronic pain post-TBI are addressed.

Concussion rates and effects on player performance in Major League Baseball players

Background

Major League Baseball (MLB) players are throwing the ball faster and hitting harder than ever before. Although some safety measures have been implemented, by decreasing the 15 days on the disabled list (DL) to the 7 days on the DL, concussion rates remain high across positions and may impact player performance. Our hypothesis was, there would be an increase in concussion incidence following implementation of the 7 day DL, but this would not have a negative impact on player’s postconcussion performance.

Study design

This is a descriptive epidemiology study.

Methods

The concussed players from 2005 to 2016 were identified from the MLB DL and verified using established new sources. Position-specific performance metrics from before and after injuries were gathered and compared to assess effects of the injury. Postconcussion performance metrics were compared before and after the 7-day DL rule implementation.

Results

A total of 112 concussed players were placed on the DL. For all position players, the batting average (BA) and on-base percentage (OBP) showed a nonsignificant decline after injury (P=0.756). Although performance statistics for pitchers declined on average, the trend was not statistically significant. Postinjury BA and OBP did not significantly change before (0.355) and after (0.313) the 7-day DL rule change in 2011 (P=0.162).

Conclusion

The incidence of reported concussion has increased with the 7-day DL rule change. Concussion incidence was highest in catchers and pitchers compared with all other players. The most common causes identified as being hit by pitch or struck by a foul ball or foul tip. While new league rules prevent collisions with catchers at home plate, injury by a foul tip was the most common cause for concussion. The shortened time spent on the DL did not negatively impact player’s performance. Further research on protective helmets for catchers may reduce concussion incidence.

A review of the effects of physical activity and sports concussion on brain function and anatomy

Physical activity has been associated with widespread anatomical and functional brain changes that occur following acute exercise or, in the case of athletes, throughout life. High levels of physical activity through the practice of sports also lead to better general health and increased cognitive function. Athletes are at risk, however, of suffering a concussion, the effects of which have been extensively described for brain function and anatomy. The level to which these effects are modulated by increased levels of fitness is not known. Here, we review literature describing the effects of physical activity and sports concussions on white matter, grey matter, neurochemistry and cortical excitability. We suggest that the effects of sports concussion can be coufounded by the effects of exercise. Indeed, available data show that the brain of athletes is different from that of healthy individuals with a non-active lifestyle. As a result, sports concussions take place in a context where structural/functional plasticity has occurred prior to the concussive event. The sports concussion literature does not permit, at present, to separate the effects of intense and repeated physical activity, and the abrupt removal from such activities, from those of concussion on brain structure and function.

Longitudinal Changes in Resting State Connectivity and White Matter Integrity in Adolescents With Sports-Related Concussion

OBJECTIVES

The aim of this study was to investigate alterations in functional connectivity, white matter integrity, and cognitive abilities due to sports-related concussion (SRC) in adolescents using a prospective longitudinal design.

METHODS

We assessed male high school football players (ages 14-18) with (n=16) and without (n=12) SRC using complementary resting state functional MRI (rs-fMRI) and diffusion tensor imaging (DTI) along with cognitive performance using the Immediate Post-Concussive Assessment and Cognitive Testing (ImPACT). We assessed both changes at the acute phase (<7 days post-SRC) and at 21 days later, as well as, differences between athletes with SRC and age- and team-matched control athletes.

RESULTS

The results revealed rs-fMRI hyperconnectivity within posterior brain regions (e.g., precuneus and cerebellum), and hypoconnectivity in more anterior areas (e.g., inferior and middle frontal gyri) when comparing SRC group to control group acutely. Performance on the ImPACT (visual/verbal memory composites) was correlated with resting state network connectivity at both time points. DTI results revealed altered diffusion in the SRC group along a segment of the corticospinal tract and the superior longitudinal fasciculus in the acute phase of SRC. No differences between the SRC group and control group were seen at follow-up imaging.

CONCLUSIONS

Acute effects of SRC are associated with both hyperconnectivity and hypoconnectivity, with disruption of white matter integrity. In addition, acute memory performance was most sensitive to these changes. After 21 days, adolescents with SRC returned to baseline performance, although chronic hyperconnectivity of these regions could place these adolescents at greater risk for secondary neuropathological changes, necessitating future follow-up. (JINS, 2018, 24, 781-792).

Concussion Symptom Prevalence, Severity and Trajectory: Implications for Nursing Practice

PURPOSE

The purpose of this study was to describe the symptom severity and trajectory in concussed children who were followed during a one year period at a concussion clinic.

DESIGN AND METHODS

A retrospective chart review was completed to describe the symptom trajectory up to three months during the recovery.

RESULTS

One hundred and thirty-six patients were included (74 female, 62 male) with a median age of 15.4years (range 13-17). The most common mechanisms of injury included: falls (19.9%), hockey injuries (15.4%), soccer (14.0%) and football injuries (6.6%). Most concussion symptoms decreased in severity or improved over time. Four symptoms including fatigue/low energy, drowsiness, concentration difficulties and irritability had the highest symptoms scores at both 28 and 84days post-injury in patients with persistent symptoms. Emotionality and nervousness/anxiousness and nausea/vomiting scores were seen to increase over time in patients with persistent symptoms.

IMPLICATIONS

Clinical use of standardized assessment tools can help caregivers track and monitor concussion symptoms over time. Appropriate management strategies need to be devised for symptoms that are prevalent or increasing over time.

Effects of concussions on visually guided motor actions: A literature review

Athletes must be able to successfully navigate the soccer pitch or hockey rink to win the game, requiring maximal cognitive resources to successfully compete. Concussions potentially deplete these resources, and the long-term impact of concussions on an individual's goal-directed visually guided behavior continues to elude the scientific community. While the acute effects on cognition and the motor system have been elucidated elsewhere, long-term effects on performance have been less clear. Additionally, most investigations into long-term postinjury motor behaviors have focused on balance and gait, with little focus on functional upper extremity movements. These arm movements require both cognitive and motor functions to successfully complete the task, such as visually guided reaching, and have received little attention. This review examines the current state of the literature to date on the long-term effects of concussions on cognitive and motor deficits affecting visuomotor behavior.

Effect of Head Impact Exposures on Changes in Cognitive Testing

Background

Gaining a better understanding of head impact exposures may lead to better comprehension of the possible effects of repeated impact exposures not associated with clinical concussion.

Purpose

To assess the correlation between head impacts and any differences associated with cognitive testing measurements pre- and postseason.

Study Design

Case-control study; Level of evidence, 3.

Methods

A total of 34 National Collegiate Athletic Association Division I men's lacrosse players wore lacrosse helmets instrumented with an accelerometer during the 2014 competitive season and were tested pre- and postseason with the Sport Concussion Assessment Tool (SCAT 3) and Concussion Vital Signs (CVS) computer-based neurocognitive tests. The number of head impacts >20g and results from the 2 cognitive tests were analyzed for differences and correlation.

Results

There was no significant difference between pre- and postseason SCAT 3 scores, although a significant correlation between pre- and postseason cognitive scores on the SCAT 3 and total number of impacts sustained was noted (r = -0.362, P = .035). Statistically significant improvements on half of the CVS testing components included visual reaction time (P = .037, d = 0.37), reaction time (P = .001, d = 0.65), and simple reaction time (P = .043, d = 0.37), but no correlation with head impacts was noted.

Conclusion

This study did not find declines in SCAT 3 or CVS scores over the course of a season among athletes who sustained multiple head impacts but no clinical concussion. Thus, it could not be determined whether there was no cognitive decline among these athletes or whether there may have been subtle declines that could not be measured by the SCAT 3 or CVS.

Undetected psychiatric morbidity among HIV/AIDS patients attending Comprehensive Care Clinic (CCC) in Nairobi Kenya: towards an integrated mental health care

BACKGROUND

Psychiatric morbidity is commonly associated with HIV disease and may have adverse effects. This aspect may be overlooked at comprehensive HIV care centers in Low and Middle-Income Countries.

OBJECTIVES

The aim of this study was to determine the prevalence of undetected psychiatric morbidity among HIV/AIDS adult patients attending Comprehensive Care Centre in a semi-urban clinic, in Nairobi, Kenya.

DESIGN

Descriptive cross-sectional study of adult HIV patients not receiving any psychiatric treatment was conducted.

PARTICIPANTS/METHODS

The participants consisted of consecutive sample of adults (n = 245) attending HIV Comprehensive Care Clinic at Kangemi Health Centre, Nairobi. The Mini International Neuropsychiatric Interview (MINI) was administered to screen for undetected psychiatric morbidity. Socio-demographic characteristics were recorded in a questionnaire. Sample descriptive analysis was performed and prevalence of undetected psychiatric morbidity calculated. Chi-square test for independence was used to examine the associations between patient characteristics and undetected morbidity. Multivariable logistic regression analysis was performed to determine independent predictors of undetected psychiatric morbidity.

RESULTS

The mean age of our participants was 37.3 years (SD 9.2) Three-quarters (75.9%) of participants were females and median duration of HIV illness was 5 years. The prevalence of (previously undetected) psychiatric morbidity was 71.4% (95% CI 65.3-77). The leading psychiatric disorders were MDD (32.2%), PTSD (18.4%), Dysthymia (17.6%), and OCD (17.6%). Overall psychiatric morbidity was associated with low income (

CONCLUSION

The burden of psychiatric morbidity in Kenyan HIV patients remains high and is most significantly associated with lower socioeconomic status. There is need to provide holistic care including screening for mental well-being all through the treatment of HIV patients in low-income settings.

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Key Words

• HIV/AIDS
• Low-income status
• Psychiatric morbidity
• Stigma

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MESH Headings Collapse

Grants

• U19 MH110001 NIMH NIH HHS
• National Institute of Mental Health

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Affiliation(s)

Pauline W. Ng’ang’a Department of Psychiatry, College of Health Sciences, University of Nairobi, P O Box 19676, Nairobi, 00202 Kenya
Muthoni Mathai Department of Psychiatry, College of Health Sciences, University of Nairobi, P O Box 19676, Nairobi, 00202 Kenya
Anne Obondo Department of Psychiatry, College of Health Sciences, University of Nairobi, P O Box 19676, Nairobi, 00202 Kenya
Teresia Mutavi Department of Psychiatry, College of Health Sciences, University of Nairobi, P O Box 19676, Nairobi, 00202 Kenya
Manasi Kumar Department of Psychiatry, College of Health Sciences, University of Nairobi, P O Box 19676, Nairobi, 00202 Kenya Research Department of Clinical Health and Educational Psychology, University College London, London, WC1E 7HB UK

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Collegiate Student Athletes With History of ADHD or Academic Difficulties Are More Likely to Produce an Invalid Protocol on Baseline ImPACT Testing

OBJECTIVE

Attention deficit hyperactivity disorder (ADHD) and other academically-relevant diagnoses have been suggested as modifiers of neurocognitive testing in sport-related concussion, such as Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT). These preexisting conditions may suppress ImPACT scores to the extent that they are indistinguishable from low scores because of poor effort. The present study hypothesized that student athletes with history of ADHD or academic difficulties produce lower ImPACT composite scores and are more likely to produce invalid protocols than those without such conditions.

DESIGN

Cross-sectional study.

SETTING

Midsized public university.

PARTICIPANTS

Nine hundred forty-nine National College Athletic Association athletes (average age = 19.2 years; 6.8% ADHD, 5.6% Academic Difficulties, 2.0% comorbid ADHD/Academic Difficulties).

INDEPENDENT VARIABLES

Three seasons of baseline ImPACT protocols were analyzed. Student athletes were grouped using self-reported histories of ADHD or academic difficulties taken from ImPACT demographic questions.

DEPENDENT VARIABLES

ImPACT composite scores and protocol validity.

RESULTS

Student athletes in the academic difficulties and comorbid groups performed worse on ImPACT composite scores (Pillai's Trace = 0.05), though this pattern did not emerge for those with ADHD. Student athletes with comorbid history were more likely to produce an invalid baseline (10.5% invalid) (χ (2) = 11.08, P = 0.004). Those with ADHD were also more likely to produce an invalid protocol (7.7% invalid, compared with 2.6% in student athletes with no history) (χ (2) = 10.70, P = 0.005).

CONCLUSIONS

These findings suggest that student athletes reporting comorbid histories or histories of academic difficulties alone produce lower ImPACT composite scores, and that those with comorbid histories or histories of ADHD alone produce invalid protocol warnings more frequently than student athletes without such histories. Future studies should further examine invalid score thresholds on the ImPACT, especially in student athletes with conditions that may influence test performance.

CLINICAL RELEVANCE

Student athletes with history of ADHD or academic difficulties may more frequently fall below validity score thresholds, suggesting caution in interpreting test performance.

Consistency and Variation in School-Level Youth Sports Traumatic Brain Injury Policy Content

PURPOSE

The purpose of the study was to examine the consistency and variation in content of high school written traumatic brain injury (TBI) policies in relation to the three key tenets of youth sports TBI laws.

METHODS

A content analysis was conducted on written TBI policies retrieved from 71 high schools currently participating in High School Reporting Information Online. Each policy was independently analyzed by two trained coders. The number and percent of the policies reflecting the three key tenets of state youth sports TBI laws were described and compared on policy enforcement (i.e., strictness of language), policy description (i.e., details and definitions of the requirements), and policy implementation steps (i.e., specific steps for implementing the requirements). Direct quotes were identified to support quantitative findings.

RESULTS

All 71 high school TBI policies contained at least two of the three main TBI law tenets, where 98.6% (n = 70) included the return to play tenet, 83.1% (n = 59) included the removal from play tenet, and 59.2% (n = 42) specified the distribution of TBI information sheets to student-athletes and their parents. Nearly half of the policies (49.3%, n = 35) required parents' signature while only 39.4% (n = 28) required students' signature on the TBI information sheet. The language exhibited wide variance across the 71 TBI policies regarding policy enforcement, policy description, and policy implementation specifications.

CONCLUSIONS

All 71 TBI policies covered at least two of the three youth sports TBI law tenets, but with considerable variation. Future research should assess variations by schools within the same state and their impact on TBI rates in school athletics.

Telomere length and advanced diffusion MRI as biomarkers for repetitive mild traumatic brain injury in adolescent rats

Mild traumatic brain injuries (mTBI) are of worldwide concern in adolescents of both sexes, and repeated mTBI (RmTBI) may have serious long-term neurological consequences. As such, the study of RmTBI and discovery of objective biomarkers that can help guide medical decisions is an important undertaking. Diffusion-weighted MRI (DWI), which provides markers of axonal injury, and telomere length (TL) are two clinically relevant biomarkers that have been implicated in a number of neurological conditions, and may also be affected by RmTBI. Therefore, this study utilized the lateral impact injury model of RmTBI to investigate changes in diffusion MRI and TL, and how these changes relate to each other. Adolescent male and female rats received either three mTBIs or three sham injuries. The first injury was given on postnatal day 30 (P30), with the repeated injuries separated by four days each. Seven days after the final injury, a sample of ear tissue was collected for TL analysis. Rats were then euthanized and whole brains were collected and fixated for MRI analyses that included diffusion and high-resolution structural sequences. Compared to the sham-injured group, RmTBI rats had significantly shorter TL at seven days post-injury. Analysis of advanced DWI measures found that RmTBI rats had abnormalities in the corpus callosum and cortex at seven days post-injury. Notably, many of the DWI changes were correlated with TL. These findings demonstrate that TL and DWI measurements are changed by RmTBI and may represent clinically applicable biomarkers for this.

Comparison of baseline ImPACT performance in amateur motocross riders to football and basketball athletes

PRIMARY OBJECTIVE

The American Motorcyclist Association requires professional riders to undergo baseline computerized neurocognitive testing (CNT) using the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) test for concussion management. It is recommended this practice be expanded to the amateur level, but limited research has explored whether baseline testing is necessary for youth when normative data is available. This study evaluates the utility of baseline testing for amateur riders by comparing their performance to those of traditional youth sports comprising normative datasets.

DESIGN/METHODS

An cross-sectional study comparing amateur motocross (N = 100) riders matched by age and sex to football (N = 100) and basketball (N = 100) athletes performance on baseline ImPACT testing.

RESULTS

ANCOVAs revealed a significant medium effect of group on measures of visual motor speed (F = 11.25, p < 0.001) and reaction time (F = 13.61, p < 0.001). Post hoc analyses revealed that motocross riders were significantly slower compared to football and basketball athletes. There were no significant differences (p > .05) between sport on measures of memory or symptoms.

CONCLUSIONS

Youth motocross riders performed significantly slower on speed measures compared to football and basketball athletes, providing preliminary support for the expansion of baseline ImPACT testing to the amateur level.

Concussion Assessment With Smartglasses: Validation Study of Balance Measurement Toward a Lightweight, Multimodal, Field-Ready Platform

BACKGROUND

Lightweight and portable devices that objectively measure concussion-related impairments could improve injury detection and critical decision-making in contact sports and the military, where brain injuries commonly occur but remain underreported. Current standard assessments often rely heavily on subjective methods such as symptom self-reporting. Head-mounted wearables, such as smartglasses, provide an emerging platform for consideration that could deliver the range of assessments necessary to develop a rapid and objective screen for brain injury. Standing balance assessment, one parameter that may inform a concussion diagnosis, could theoretically be performed quantitatively using current off-the-shelf smartglasses with an internal accelerometer. However, the validity of balance measurement using smartglasses has not been investigated.

OBJECTIVE

This study aimed to perform preliminary validation of a smartglasses-based balance accelerometer measure (BAM) compared with the well-described and characterized waist-based BAM.

METHODS

Forty-two healthy individuals (26 male, 16 female; mean age 23.8 [SD 5.2] years) participated in the study. Following the BAM protocol, each subject performed 2 trials of 6 balance stances while accelerometer and gyroscope data were recorded from smartglasses (Glass Explorer Edition). Test-retest reliability and correlation were determined relative to waist-based BAM as used in the National Institutes of Health's Standing Balance Toolbox.

RESULTS

Balance measurements obtained using a head-mounted wearable were highly correlated with those obtained through a waist-mounted accelerometer (Spearman rho, ρ=.85). Test-retest reliability was high (intraclass correlation coefficient, ICC2,1=0.85, 95% CI 0.81-0.88) and in good agreement with waist balance measurements (ICC2,1=0.84, 95% CI 0.80-0.88). Considering the normalized path length magnitude across all 3 axes improved interdevice correlation (ρ=.90) while maintaining test-retest reliability (ICC2,1=0.87, 95% CI 0.83-0.90). All subjects successfully completed the study, demonstrating the feasibility of using a head-mounted wearable to assess balance in a healthy population.

CONCLUSIONS

Balance measurements derived from the smartglasses-based accelerometer were consistent with those obtained using a waist-mounted accelerometer. Additional research is necessary to determine to what extent smartglasses-based accelerometry measures can detect balance dysfunction associated with concussion. However, given the potential for smartglasses to perform additional concussion-related assessments in an integrated, wearable platform, continued development and validation of a smartglasses-based balance assessment is warranted. This approach could lead to a wearable platform for real-time assessment of concussion-related impairments that could be further augmented with telemedicine capabilities to integrate professional clinical guidance. Smartglasses may be superior to fully immersive virtual reality headsets for this application, given their lighter weight and reduced likelihood of potential safety concerns.

Cortical and Physical Function after Mild Traumatic Brain Injury

PURPOSE

The aim of this study was to prospectively examine the association between intracortical inhibition and functional recovery after mild traumatic brain injury (mTBI).

METHODS

Twenty individuals with mTBI and 20 matched control participants were assessed using transcranial magnetic stimulation, the Attentional Network Test, and gait analysis. Hierarchical linear modeling was used to longitudinally examine potential differences between groups and relationships in the pattern of recovery in cortical silent period (CSP) duration, cognitive reaction time, and single- and dual-task walking speeds across five testing time points. Individuals with mTBI were assessed within 72 h of injury, and again at 1 wk, 2 wk, 1 month, and 2 months postinjury. After initial testing, control participants followed a similar timeline.

RESULTS

At the 72-h time point, the group with mTBI had longer reaction time (b = -91.76, P = 0.01), similar single-task walking speed (b = 0.055, P = 0.10), and slower dual-task walking speed (b = 0.10, P = 0.012) compared with control participants. The CSP duration also tended to be longer in individuals with mTBI than controls at the 72-h time point (b = -16.34, P = 0.062). The change is CSP duration over time was not significantly associated with the change in reaction time (b = -0.19, P = 0.47), single-task walking speed (b = 0.0001, P = 0.53), or dual-task walking speed (b < 0.001, P = 0.68).

CONCLUSION

Although cognitive and motor functions were significantly impaired in the mTBI group acutely after injury, levels of intracortical inhibition were not associated with recovery in either functional domain.

Game Schedules and Rate of Concussions in the National Football League

Background

Concussion prevention in the National Football League (NFL) is an important priority for player safety. The NFL now has modified game schedules, and one concern is that unconventional game schedules, such as a shortened rest period due to playing on a Thursday rather than during the weekend, may lead to an increased risk of injuries.

Hypothesis

Unconventional game schedules in the NFL are associated with an increased rate of concussion.

Study Design

Descriptive epidemiological study.

Methods

This study analyzed concussions and game schedules over the NFL regular seasons from 2012 to 2015 (4 years). Documented numbers of concussions, identified by use of the online database PBS Frontline Concussion Watch, were summarized by regular-season weeks. Association of days of rest and game location (home, away, or overseas) with the rate of concussion was examined by use of the χ² test. Logistic regression analysis was performed to examine the relationships of days of rest and home/away games to the risk of repeated concussions, with adjustment for player position.

Results

A total of 582 concussions were analyzed in this study. A significantly greater number of concussions occurred in the second half of the season (P < .01). No significant association was found between the rate of concussion and the days of rest, game location, or timing of the bye week by the team or the opponent (P > .05). Game schedules were not significantly associated with the occurrence of repeat concussions (P > .05).

Conclusion

Unconventional game schedules in the NFL, including playing on Thursday and playing overseas, do not seem to put players at increased risk of concussions.

Reliability and Concurrent Validity of Select C3 Logix Test Components

We sought to investigate the one-week and within-session reliability of the instrumented balance error scoring system test and the concurrent validity/one-week reliability of two neurocognitive assessments available through C3 Logix. (n = 37) Participants completed two balance error scoring system tests separated by the Trails A, Trails B, and Symbol Digit Modality test available through C3 Logix, and with paper and pencil. We found that the instrumented balance error scoring system test demonstrated strong one-week reliability and that neuropsychological tests available through C3 Logix show acceptable concurrent validity with standard (comparable) paper and pencil measures.

Improvements in balance control in individuals with PCS detected following vestibular training: A case study

Concussed individuals have been found to experience balance deficits in the anterior-posterior (AP) direction as indicated by greater Center of Pressure (COP) displacement and velocity. One possible reason for this change in balance control could be due to damage to the lateral vestibulospinal tract which sends signals to control posterior muscles, specifically ankle extensors leading to compensatory torques about the ankle. The purpose of the study was to quantify balance assessments in individuals experiencing persistent post-concussion symptoms (PCS) to determine balance control changes following a vestibular training intervention. Participants (N=6,>26days symptomatic), were tested during their first appointment with a registered physiotherapist (PT) and during each follow up appointment. Participants were prescribed balance, visual, and neck strengthening exercises by the PT that were to be completed daily between bi-weekly appointments. Balance assessments were quantified using a Nintendo Wii board to record ground reaction forces. Participants completed 4 balance assessments: 1) Romberg stance eyes open (REO); 2) Romberg stance eyes closed (REC); 3) single leg stance eyes open (SEO); and 4) single leg stance eyes closed (SEC). The balance assessments were conducted on both a firm and compliant surfaces. Significant improvements in balance control were noted in ML/AP displacement and velocity of COP for both SEC and Foam REC conditions, with additional improvements in AP velocity of COP for Foam REC and in ML displacement of COP during Foam SEC. Overall, findings indicate that objectively quantifying balance changes for individuals experiencing persistent PCS allows for a more sensitive measure of balance and detects changes unrecognizable to the naked eye.

Anxiety and Mood Clinical Profile following Sport-related Concussion: From Risk Factors to Treatment

Conceptual models for assessing and treating sport-related concussion (SRC) have evolved from a homogenous approach to include different clinical profiles that reflect the heterogeneous nature of this injury and its effects. There are six identified clinical profiles, or subtypes from SRC, and one such clinical profile is the anxiety/mood profile. Athletes with this profile experience predominant emotional disturbance and anxiety following SRC. The purpose of this targeted review was to present an overview of the empirical evidence to support factors contributing to the anxiety/mood profile, along with methods of evaluation and treatment of this clinical profile following SRC. We discuss the potential underlying mechanisms and risk factors for this clinical profile, describe comprehensive assessments to evaluate concussed athletes with an anxiety/mood clinical profile, and explore behavioral and other interventions for treating these athletes. Although there is limited, but growing empirical evidence for the anxiety/mood clinical profile following SRC, understanding this clinical profile is germane for clinicians who are treating athletes with emotional sequelae after SRC.